1. Field of the Invention
The present invention relates to an electronic musical instrument that generates a musical tone according to a musical tone signal generated based on an operated state of an operating element for musical performance.
2. Description of the Related Art
As a conventional electronic musical instrument of the above-mentioned type, there has been known one disclosed e.g. in Japanese Laid-Open Patent Publication (Kokai) No. 2013-77000. This conventional electronic musical instrument is formed by adding functions of an electronic piano to an acoustic upright piano. The electronic musical instrument is provided with a keyboard, a soundboard, a vibration exciter, and a controller, and has a plurality of operation modes including a weak tone mode. In the weak tone mode, key depression information is detected by a sensor, and a detection signal indicative of the key depression information is input to the controller. The controller, which is implemented e.g. by a CPU, drives the vibration exciter according to the key depression information detected by the sensor. This causes the vibration exciter to vibrate the soundboard, whereby a musical tone is generated.
As shown in FIG. 8, an upright electronic piano constructed as above generally has a soundboard SB formed in a rectangular shape, and upper, lower, right, and left ends of the soundboard SB are secured to the front surface of a rim FR of the electronic piano by upper screws UB, lower screws DB, left screws LB, and right screws RB, respectively. Note that in FIG. 8, each of the upper to right screws UB to RB is illustrated on a slightly enlarged scale for convenience' sake.
The upper screws UB and the lower screws DB are arranged such that the location of each of the upper screws UB and the location of each of the lower screws DB are opposed to each other in symmetrical relation in a vertical direction, and the left screws LB and the right screws RB are arranged such that the location of each of the left screws LB and the location of each of the right screws RB are opposed to each other in symmetrical relation in a horizontal direction. For this reason, the conventional upright electronic piano suffers from the following problem: The screws UB to RB for use in mounting the soundboard SB are arranged as above and consequently the fixed ends of the upper, lower, right, and left ends of the soundboard SB are regularly positioned, and hence when the soundboard SB is caused to be vibrated by the vibration exciter in accordance with key depression, the soundboard SB easily resonates, which causes a large peak dip in the frequency characteristic of a musical tone, so that it is impossible to obtain excellent musical sound.